Many retail and warehouse facilities disseminate two-way radios among their employees to facilitate their operations. For example, a large retail facility may distribute two-way radios to each of its customer-service personnel, so that they may be alerted in the event that a particular customer is in need of assistance. In such an event, a transmission is broadcast to radios carried by each of the customer-service personnel, and a particular customer service representative responds by transmitting his intention to assist the client in need, so that the remaining representatives can pursue other activities. Two-way radios are used because they promote efficiency, yet are relatively inexpensive, reliable, and allow for simple one-to-many communication.
A particular drawback to the use of two-way radios in retail settings is that they are prone to employee theft. Such theft can prove expensive over time. For example, a major retail store may require as many as fifty or more radios. Over the duration of a year, as much as a third of those radios are stolen by employees (or others) for private use. These radios must be replaced at significant expense to the retailer.
One theft prevention strategy that has been employed in the past is to design the two-way radios to transmit on a first frequency, but receive on a second frequency. Thus, without the aid of another device, none of the radios can receive the transmission of another radio. To permit communication within the retail store, a repeater is employed. The repeater receives the radio transmissions on the first frequency and re-transmits those transmissions on the second frequency, so that they may be received by the radios in the retail space. Once out of range of the repeater, the radios are inoperative, because they are unable to communicate with each other. Thus, the motivation for stealing the radios is eliminated.
The above-described repeater scheme possesses certain drawbacks, however. In a retail setting, two-way radios may be used amongst stock room personnel, amongst security personnel, and amongst greeters. Oftentimes, each group of personnel is assigned their own frequency for transmission (one frequency for security personnel, and another frequency for customer service personnel, for example). For the above-described repeater scheme to work in such a setting, multiple repeaters need to be deployed, each operating on a unique set of frequencies. Such a scheme is expensive to establish and expensive to maintain, because of frequency variations from store to store.
As is evident from the preceding discussion, there is a need for a simple, inexpensive scheme for deterring theft of two-way radios from retail settings. A desirable scheme is able to work with existing radios in a convenient and cost-effective manner.